Adding ceramic polishing waste as filler to reduce paste volume and improve carbonation and water resistances of mortar

Abstract

The use of ceramic waste in concrete/mortar production as aggregate replacement or cement replacement has been under consideration in the last decade to find an effective way to tackle the growing hazard of ceramic waste disposal. In this study, the authors reutilize ceramic polishing waste (CPW) as a filler to replace an equal volume of cement paste in mortar while keeping the mixture proportions of the cement paste unchanged, i.e., in a new way as paste replacement. This mixture design strategy allows a larger amount of CPW to be added to substantially reduce the paste volume, cement and carbon footprint. The mortar mixes so produced had been subjected to carbonation and water absorption tests, and the results showed that as paste replacement, the CPW can significantly enhance the carbonation and water resistances, in addition to the environmental benefits of reducing waste, cement and carbon footprint. Regression analysis of test results indicated that for carbonation resistance, the cementing efficiency factor of the CPW was around 0.5, whereas for water resistance, the cementing efficiency factor was higher than 1.0 at low CPW content and lower than 1.0 at high CPW content.